9 research outputs found

    Failure of Micaceous Waste Tailings Dam

    Get PDF
    The paper describes the failure and reconstruction of an 80 ft. high, 8 acre tailings impoundment in Western North Carolina. The darn was constructed using the upstream method of construction. The coarse fraction of the tailings was used as embankment construction materials; these consisted of coarse to fine sands. The fine fraction tailings consisted of low density, relatively low plasticity, layered fine sands and fine sandy silts with frequent inter bedding of micaceous silty clays. Although a 20.0 ft. section of the darn failed, the fine saturated tailings did not liquefy but rather slumped into the breach. Reconstruction was complicated because there was no convenient access to the toe of the darn. Since this darn had been previously studied and found to be marginally stable, the failure reinforces the need for the engineer to keep accurate records of telephone conversations and other correspondence to help protect himself from having any liability in the failure

    International Consensus Statement on Rhinology and Allergy: Rhinosinusitis

    Get PDF
    Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR‐RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR‐RS‐2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence‐based findings of the document. Methods: ICAR‐RS presents over 180 topics in the forms of evidence‐based reviews with recommendations (EBRRs), evidence‐based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICAR‐RS‐2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence‐based management algorithm is provided. Conclusion: This ICAR‐RS‐2021 executive summary provides a compilation of the evidence‐based recommendations for medical and surgical treatment of the most common forms of RS

    Functional evaluation of the various calculation methods for precompression stress

    No full text
    Precompression stress (sigma(p)) is commonly used as an indicator for the load carrying capacity of a soil and its stress history. Several calculation methods have been proposed to determine sigma(p), but they have proven to be not interchangeable. The aim of this study was to perform a functional evaluation of seven existing methods to test which method would be most recommended to assess soil strength in cultivated fields. This was achieved by investigating the relation of the obtained sigma(p) of undisturbed soil samples to other soil properties and stress history. Additionally, the robustness of the methods was evaluated by checking their sensitivity to perturbation of the measured strains. The two most commonly used methods, the Casagrande method and Gompertz model fit method, were found to be the least suitable to calculate sigma(p). These methods lack robustness and do not yield a significant relation with the relevant soil properties or stress history. Better results were obtained with Intersecting linear regressions or at the inflection point of a fourth-degree polynomial
    corecore